The present invention relates to a unique process and apparatus for making shearform matrix material resulting from transformation of the morphology of feedstock material.
The art of material processing has developed significantly in recent years. In U.S. Pat. No. 4,855,326 various substances having pharmological properties are combined with saccharides and spun to produce a readily water-soluble product. Other disclosures which relate to spinning substances with one or more saccharides are found in U.S. Pat. No. 4,873,085, U.S. Pat. No, 5,034,421, U.S. Pat. No. 4,997,856 and U.S. Pat. No. 5,028,632. U.S. Pat. No. 5,034,421 discloses spun matrix systems containing medicaments having predetermined release patterns.
The examples in the disclosures set forth above describe processing feedstock material by subjecting it to high speed spinning on a spinning head in which the substance is also subjected to heating against a heating element. The change of temperature is quite rapid, which is believed to be occasioned by the spinning head quickly and efficiently spreading the feedstock material against the heating element circumferentially disposed around the perimeter of the spinning head. Thus, extensive surface contact of the feedstock is provided against the heating element itself while being spun.
The feedstock material is heated sufficiently to create an internal flow condition which permits part of the feedstock to move at what is believed to be a subparticle level with respect to the rest of the mass and exit openings provided in the perimeter of the spinning head. The centrifugal force created in the spinning head flings the flowing feedstock material outwardly from the head so that it reforms with a changed structure. The force required to separate and discharge flowable feedstock is only the centrifugal force which results from the spinning head. These examples describe one approach to producing a novel matrix material.
A further reference, U.S. Pat. No. 5,380,473, sets forth a process in which the temperature of a nonsolubilized feedstock carrier is increased to a point where it will undergo internal flow, followed by ejecting a stream of the feedstock and then subjecting it to disruptive fluid shear force which separates it into separate parts or masses which have a transformed morphology. Also disclosed in the '473 reference is an apparatus with a high pressure nozzle for changing the morphology of the feedstock. The nozzle is directed downwards which has advantages in that material is being expunged therefrom to coincide with the downward pull of gravity. However, it has now been discovered that on a commercial scale a downwardly-directed nozzle must be suspended from a rather large height so that the large quantity of exiting material can fully and completely dry in the air before reaching a bottom collection mechanism. This necessitates extra space and volume in a processing center.
It is an object of the present invention to overcome certain drawbacks which are associated with the above-cited apparatus and procedures. It is also an object of the present invention to provide improvements over the technology previously set forth in the art.